Power-to-Gas: Bridging the Electricity and Gas Networks

By Mohammad Amin Mirzaei, Mahdi Habibi, Vahid Vahidinasab and Behnam Mohammadi-Ivatloo

Power-to-Gas: Bridging the Electricity and Gas Networks introduces the concept of Power-to-Gas (P2G) technologies in the Whole Energy System framework and related Vector-Coupling Technologies (VCTs). The boo provides a comprehensive approach to the economic, technical and environmental evaluation of P2G technology to make more effective use of the surplus power of renewable units. It covers converting electricity to hydrogen or methane, and the challenges, analytical solutions and future trends of P2G applications. Moreover, the reference features technology overviews and literature reviews in each chapter, along with concepts, appropriate definitions, fundamentals and contexts in the energy systems.

Finally, modeling issues and requirements for analysis Gas and Power Vector-Coupling Technologies are presented and supported by real-world case studies and experimental examples. By uniquely analyzing issues from the whole energy system perspective, this book plays a pivotal role in supporting researchers and academicians in electrical, mechanical and energy engineering in their long-term decarbonization strategies.

• Includes a reliability assessment of cyber-physical power applications
• Presents practical methods, along with evidence from applications to real-world and simulated coupled energy systems
• Provides sample computer codes/pseudocodes and analytical examples for the presented methods

• Language: English
• Publisher: Academic Press
• Release date: Apr 22, 2023
• ISBN: 9780323906548

Mohammad Amin Mirzaei

Mohammad Amin Mirzaei received a B.Sc. in electrical engineering from Ilam University, Iran in 2015, and an M.Sc. in electrical engineering from Sahand University of Technology, Tabriz, Iran in 2018. Currently, he is a research assistant at the University of Tabriz, Tabriz, Iran. The main areas of his interests are energy market-clearing, risk-based energy management, emerging energy storage technologies, demand response, and integrated energy systems. He has authored and co-authored more than 25 technical publications (more than 12 of them were published in international journals) in his domain of interest, 4 book chapters. He is currently working on multi-carrier energy systems. He also submitted more than 15 papers to international journals that related to the role of emerging energy resources in multi-energy systems.

Book preview

Chapter One: Whole system approach to energy

Abstract

The holistic approach in the management of multi-energy systems contributes to considering interoperability and enhancing system efficiency by using modern equipment such as power-to-X technology. Converted energy from renewable resources, called green products, can be stored and used in other energy forms such as hydrogen or supplementary products. This chapter describes the whole system approach to energy focusing on cross-sector energy solutions, and it illustrates different aspects of energy coupling and the Power-to-X concept. Besides, this chapter will evaluate the trend of new projects and the direction of investments worldwide in line with the international zero-carbon target and the place of supplementary green products.

Keywords

Engineering solutions; Integrated approach; Interoperability; Multi-carrier energy; New technologies; Zero-carbon

1.1. Introduction

While 200 years ago, James Watt used the whole system view in designing to enhance efficiency and reduce costs, nowadays, the sustainable perspective of our planet's resources demands to go further [1]. We should protect the natural resources, environment, and communities for future generations. Hence, sustainable developments will improve the environmental condition and human health alongside economic perspective and increasing natural capital. Achieving actual sustainable development is not possible with either a comprehensive or a one-dimensional approach, and it highly depends on interactive systems collaboration. Such an integrated point of view can facilitate achieving goal seven of the UN on facilitating access to affordable, reliable, sustainable, and modern energy for all [2]. To achieve this goal, we must creatively rethink the principles of our designs, investment, and operation based on an integrated approach. The integrated approach must be in a way that reduces adverse effects related to conventional developments and create significant savings in capital and operational costs. For example, the concept of a system of systems tries to enhance the system efficiency by bringing together multiple systems with their own goals, management, and resources for a task that none of them can handle in isolation [3]. A Whole System Approach (WSA) in the energy context is essential to balance energy innovations and sustainability and in order to bridge existing energy management options and future sustainability goals. In this regard, the use of new methods for conventional technologies and the development of new technologies are suggested as engineering solutions to achieve this goal [4]. Moreover, the new concepts such as energy hubs and multi-carrier energy systems can be categorized as the WSA view in the energy context [5]. So, a new design is needed based on a holistic view, and this book outlines the related and potential aspects in the context of cross-border interoperability of energy systems.

1.2. What is the whole system approach to energy?

The holistic view in operational planning of energy systems means considering the social net benefit for the entire energy system, which is in line with considering policies and objectives to motivate system operators to include the consequences of their decisions on other parties in the value chain [6]. The holistic view in the energy sector is known as the whole system approach (WSA) to energy. The WSA to energy seeks an efficient way to consider the coordinated operating of energy systems that consist of taking steps toward various forms of clean energy and making the best decisions to benefit all participants [7]. The WSA tries to find a balance between reliability, affordability, and sustainability for worldwide access to energy (the energy trilemma described in Fig. 1.1); So, it is necessary to consider the interdependencies within energy sectors rather than in isolation [8]. The WSA supports holistic views in government policies to reach sustainable goals such as commitments arranged by the Paris agreement.

1.3. Application of whole system approach to energy in operation planning

Traditionally, many countries operate the energy systems (electricity, gas, heat, transportation, etc.) independently, and limited interactions, including the provision of fuel (gas or liquid fuels), are deemed by the UK and some European energy systems. The Council of European Energy Regulators (CEER) incorporates the integration of energy systems, e.g., electricity, heat, and gas sectors, as a layer of the WSA to energy (so-called cross-system-approach) where the decision or policy in an energy system may be lead to suboptimal solutions in other energy sectors [6]. Also, CEER believes there is an urgent and growing need to take the WSA view in managing the electricity and gas systems [9]. As an example of the WSA approach in system operation, the rapid response time of electric vehicle batteries can provide balancing services as an alternative for fast response generators. Simultaneously, this can strengthen sustainability by reducing the curtailed amount of green renewable energy [10].

The principles of WSA for facilitating cross-border energy trade and optimizing the use of interconnection are explained in network codes and guidelines [11,12]. Also, the Agency for the Cooperation of Energy Regulator (ACER) deems it necessary to develop scenarios for a broader collaboration of gas and electricity in long-term studies up to the year 2050 [13]. As an instance of running platforms, a consortium was established in 2017, called the North Sea Wind Power Hub (NSWPH), including companies of Energinet, Gasunie, and TenneT, to find a holistic approach to effectively lead transmission system operators of the North Sea countries for energy transition and climate targets under the Paris agreement [14].

1.3.1. Economic perspective

In order to support the multi-vector energy concept and its applications, there is a need to establish a balance execution between platforms required for short-term and long-term economic features. The long-term perspective is required for bringing stability to investments on a large scale and the need to provide adequate profit to market participants in the short term to enable the development of successful businesses [10]. In this way, the application of Power-to-X facilities eases the absorption of redundant amounts of renewable generations. Also, it provides additional profits by supplying innovative products such as hydrogen, methane, electricity, etc., that can be used as fuel or ancillary services.

Following the decarbonization target, large budgets are invested in renewable generations, and variability of their product may lead to incurring large constraint payments due to the coincidence with congestion in the power tie-lines. The energy conversion and vector coupling storage devices can efficiently remove the potential constraint payments, and additional services can enhance operational efficiency from the economic perspective [15].

As a sustainable WSA solution, the development of the market platform and deployment of potential ancillary services can improve the business cases for Power-to-X projects, which currently earn a small share of the potential revenue.

1.3.2. Net-zero target

Based on the 2050 net-zero emission target, the WSA principles can support the achievement of better decisions that are more compatible with environmental and economic aspects [7,16,17]. In addition, the interoperability and WSA view can enhance the efficiency and unleash the potential benefits of cross-border energy trading with the implementation of the third package. In order to achieve a low-carbon transition, growing attention is raised to developing interactions between sectors of energy systems such that it can make additional services available across borders. The benefits of the application of WSA in transition to low-carbon with high penetration of RESs are investigated in Ref. [18] for the UK integrated operating of electricity and heat systems.

1.3.3. Balancing services

Electricity is shifting to low-carbon renewable productions, which are often more variable [15]. A scenario anticipated by the UK government considers 54.7% of annual demand supplied by intermittent renewable generation in 2030, and motivated by a low-carbon view, a WSA is adopted in Ref. [19] to value the share of bulk energy storage on the UK energy system. While the changes are mainly in electricity, there are potential consequences for the gas system [9]. In addition, further changes will be seen by growing injections of hydrogen and biogases into the gas networks [20]. The services provided by vector coupling equipment, including Power-to-X elements, can be used for grid balancing and reducing renewable energy curtailments [10].

1.3.4. Vector coupling storage

There is extensive literature that considers electrolysis and gas networks as long-term vector coupling storage for electrical energy in the form of hydrogen [10]. Also [21], studies a multi-vector approach to energy management and uses the ability of natural gas pipelines to store energy and heat propagation time delay in the heating system as network flexibility. The concept of coupling storage offers an innovative solution to get rid of the constraints limiting the storage of electrical energy.

1.4. Electricity and gas interoperability: weaknesses and drivers

After the COVID-19 crisis, the gas network companies of Great Britain, with 23 million domestic consumers (85% of Britain's homes), requested a £904m investment for economic recovery and getting back on a commitment package based on the zero-carbon target by 2050 [22]. The gas network is also expected to transform from methane natural gas to zero-carbon biomethane and green hydrogen.

Currently, there is a challenging task to displace or come up with existing single-vector energy approaches. On the other hand, many technologies related to the interoperability of multi-vector energy systems have not been commercialized or have encountered obstacles that prevent increasing market penetration. Although electrolyzer devices are identified as a promising solution with a high level of flexibility, the high capital cost of the infrastructures limits their application [10].

Traditionally, in the UK, many homes use gas for heating due to efficiency and relatively low cost of gas boilers, extensive connection to the gas grid, and low price of natural gas. Relying on a one-vector energy system is not desirable based on reliability indices and UK's energy delivery targets. Hence, it is essential to adopt multi-vector solutions by developing new business models, value chains, and alternative suppliers [10].

1.5. The role of energy conversion and vector-coupling technologies

Recently, it has been speculated that the energy consumed during the fabrication of renewable resources, specifically wind turbines and silicon-based solar cells, is much more than the energy they produce [23]. Although a wide range of research investigates the development of photovoltaic systems, the natural properties of semiconductors in silicon-based solar cells limit their efficiency by almost 26%. However, the commercial panels have efficiencies between 15% and 20% [24]. The output of wind turbines is far below their maximum capacity, and it is limited to the range from 26% to 52%, and the average capacity factor was 35% for projects built in the US by 2019